1. Field
Example embodiments of the present invention relate in general to the field of method for a multi-input multi-output (MIMO) communication in a large-scale antenna system and more specifically to a method for MIMO capable of maximizing the frequency efficiency of uplink and downlink while requiring less channel state information in a large-scale antenna MIMO channel environment having an antenna correlation.
2. Description of Related Art
Beyond 4G (B4G) mobile communication needs to be provided with a frequency efficiency ten times higher than that of 4G systems such as 3GPP Long Term Evolution (LTE). As a physical layer technology required to attain the frequency ten times higher than that of 4G systems, network multi-input multi-output (MIMO), interference alignment, relay network, heterogeneous network and large-scale antenna technologies are considered.
The present invention relates to a massive MIMO (or a large-scale antenna) system that is capable of significantly enhancing the frequency efficiency. The existing large-scale antenna system is implemented based on a time division duplex (TDD) scheme. However, when a frequency division duplex (FDD) is used, a great number of reference signals as well as wireless resources for feedback of channel state information are required for a large-scale antenna transmitter to obtain channel state information.
In addition, as more and more users are simultaneously serviced by a large-scale transmitting antenna, the computational complexity in scheduling and precoding is significantly increased when compared to the existing systems.